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Abstract:
Abstract: Event-related potentials (ERPs) were recorded
during the test phase of a recognition memory task. At study, words
were presented in negatively or neutrally toned sentences. Two
topographically and temporally distinct, positive-going ERP effects
('left parietal' and 'right frontal' effects) differentiated the
ERPs elicited by correctly recognised old words from the ERPs
elicited by correctly rejected new words. These ERP old/new
differences were contrasted according to the emotional context that
had been associated with the old words at study. Both left parietal
and right frontal old/new effects were larger and more sustained
during retrieval of words that had been studied in negative
sentences. A subsequent event-related fMRI study employed a very
similar design, but also included words presented in an emotionally
positive context. Relative to the retrieval of words that had been
studied in neutral sentences: 1) words studied in negative
sentences were associated with increased activation in the right
dorsolateral prefrontal cortex, amygdala and hippocampus; 2) words
studied in positive sentences were associated with increased
activation in several prefrontal regions, including bilateral
orbitofrontal cortex. The findings suggest that words studied in
emotionally toned encoding contexts engender more extensive
recollective and post-retrieval processing in episodic memory than
do words associated with a neutral context, and in addition
activate emotion-specific brain networks.
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